The main benefit of this Core facility to the Program Project is that it provides animals with uniform surgical and molecular manipulations to all the Projects tnat require them. Thus, animals will be treated identically from the time of their mothers' arrival to the facility to the time they are shipped to various Projects. In addition, the neurons manipulated in these animals will have been done so with the same preparations of shRNA and expression plasmids. This is important not only from an anatomic perspective where it is hoped that inter-individual variability in injection size and location is minimizedbut also from the point of view of the developmental history of the animal, an especially important factor for animals undergoing behavioral testing. Live animals will be used by Projects I and IH, and perfused brains will be snipped to Project II. The Core has been successfully performing these in utero electtoporations surgeries and shRNA design and use for 7 years.